ISA’s SLP® immunotherapeutics are rationally designed, off-the-shelf, synthetic peptides. Between 20 to 50 amino acids in length, they are longer than conventional peptide immunotherapeutics, and hence are optimal for an efficient and prolonged presentation by antigen-presenting cells. Furthermore, the greater length of SLP®s allows the full array of HLA alleles (no HLA-restriction) to be used, thereby enabling an SLP® immunotherapeutic to activate the immune system of all human beings, irrespective of individual HLA types. A typical SLP® product contains between 4 and 13 different carefully selected long peptides. It thereby covers the most immunogenic regions of a therapeutic target and contains epitopes for the efficient induction of both CD4 and CD8 T cell responses.
ISA Pharmaceuticals is the first company to decipher the mode of action and the immunopharmacology of its compounds. As a result, the immunotherapeutics are optimized in terms of length, antigen selection, dosage, administration, timing of the therapeutic intervention, etc. They are also designed to contain an optimal number of T cell epitopes in order to trigger both CD8 killer and CD4 helper cells, avoid antigenic competition and provide an improved internal reservoir of antigens within dendritic cells. Therefore, SLP® immunotherapeutics are broadly applicable to a variety of targets, including cell surface, secreted and intracellular disease-related proteins.
In cancer, antigens are carefully chosen to make sure they are essential for tumor growth and cover the most immunogenic regions of the tumor cells. They are therefore ideally suited to exert therapeutic activity by themselves and to provide optimal synergy with standard cancer treatments such as chemotherapy.
SLP® immunotherapeutics are fully synthetic, off-the-shelf compounds. No ex vivo manipulation of dendritic cells (DC) is required, because efficient DC-targeting is achieved directly in vivo.